It has long been known to use inorganic oxygen compounds, such as, for example, titanium(IV) oxide and zinc oxide, as absorbers of ultraviolet light, for example in cosmetic sun protection agents or in plastics materials, paints and surface coatings. Zinc oxide is used to a particularly high degree because—unlike titanium(IV) oxide—it does not possess photocatalytic properties.
However, it is disadvantageous that the absorption edge of zinc oxide is at about 380 nm, so that satisfactory absorption in the longer-wave UVA range is not possible.
The primary object of the present invention was, therefore, to provide an inorganic UV absorber which exhibits a high absorption capacity even in the longer-wave UVA range.